package offer;

public class LowestCommonAncestor_68 {
    public TreeNode lowestCommonAncestor(TreeNode root, TreeNode p, TreeNode q) {
        if(root == null) return null;
        if( p == root || q == root){
            return root;
        }
        TreeNode left = lowestCommonAncestor(root.left,p,q);
        TreeNode right = lowestCommonAncestor(root.right, p, q);
        if(left == null){
            return right;
        }
        if(right == null){
            return left;
        }
        return root;


    }
    public class TreeNode {
        int val;

        TreeNode left;

        TreeNode right;

        TreeNode(int x) { val = x; }
    }
}
